REVERSIBILITY OF ALKENE OXYMERCURATION

It has been shown that deoxymercuration (conversion of an α-oxyorganomercurial to the alkene) is a second-order reaction dependent on concentration of the mercurial and of the deoxymercurating acid. Moreover the rate of deoxymercuration increases with basic strength of the alkoxy substituent in the mercurial. This tendency would indicate that the rate was dependent on the strength of the acid used for deoxymercuration. The supposition has been proved by use of trifluoroacetic acid which decomposes α-2-methoxycyclohexylmercuric trifluoroacetate more slowly than does hydrochloric acid. The trifluoroacetoxymercurial decomposes to the extent of 35% whereas its synthesis is effected in 60% maximum yield from cyclohexene and mercuric trifluoroacetate. A measurable equilibrium is thus attained in this oxymercuration, though not necessarily because of a simple reversible reaction.